| Severn Aviation Limited | Extraterritorial | 2016 |
| SF Renovations (SW) Limited | Construction | 2026 |
| Shalom Boconnoc Limited | Health & social care | 2014 |
| Shaping Wisdom Limited | Professional & scientific | 2012 |
| Sharmans Exterior Cleaning Ltd | Administrative & support | 2025 |
| SHH TOT Limited | Information & communication | 2015 |
| Shine (Bristol) Limited | Administrative & support | 2002 |
| Shivapur UK Ltd | Hospitality | 2022 |
| Sibley & Co. Ltd | Construction | 2025 |
| Silver Dawn Associates Limited | Information & communication | 2024 |
| Silver Guinea Holdings Ltd | Construction | 2020 |
| Simessa Tradings and Lettings Ltd | Wholesale & retail | 2025 |
| Simon Truscott Carpentry Limited | Construction | 2014 |
| SJ Homes & Properties Ltd | Real estate | 2025 |
| SJ Tools Ltd | Wholesale & retail | 2019 |
| SJS Groundscare Services Ltd | Administrative & support | 2020 |
| SKC Rock Ltd | Hospitality | 2019 |
| Skeber Ltd | Real estate | 2018 |
| Skyber Limited | Health & social care | 2014 |
| Skymark Southwest Limited | Professional & scientific | 2025 |
| Slate & Gray Ltd | Construction | 2019 |
| Smeeby Ltd | Administrative & support | 2011 |
| Smiths Coaches (Liskeard) Limited | Transport & logistics | 1998 |
| Snell & Cowling Limited | | 1947 |
| Sneyd Mining LLP | | 2021 |
| SNR Building SW Ltd | Construction | 2022 |
| Soakology Ltd | Wholesale & retail | 2026 |
| Social Impact Software Ltd | Information & communication | 2024 |
| Sola Sports Limited | Wholesale & retail | 2002 |
| Souchtech Limited | Manufacturing | 2022 |
| Soul Studios Collective Limited | Education | 2024 |
| Sound Being Ltd. | Other services | 2023 |
| South East Cornwall Fitness Limited | Arts & recreation | 2026 |
| South East Cornwall Multi Academy Regional Trust | Education | 2011 |
| South West Adventure on the Move Limited | Education | 2017 |
| South West Business Systems Limited | Information & communication | 2023 |
| South West Cleaning Solutions Ltd | Administrative & support | 2025 |
| South West Hygiene Limited | Extraterritorial | 2005 |
| South West Solar Repairs Limited | Manufacturing | 2020 |
| Southwest Creative Services Ltd | Arts & recreation | 2019 |
| Southwest Roofing Specialists Ltd | Construction | 2025 |
| Spa Training (UK) Ltd | Education | 2011 |
| Sparkly Laundry by Spick and Span Ltd | Administrative & support | 2025 |
| Spartan Build Ltd | Construction | 2023 |
| Specialist Detection Dogs (UK) Limited | Administrative & support | 2009 |
| Specialist Wildlife Rescue & Rehoming Services CIC | Agriculture & fishing | 2026 |
| Specialist Wildlife Services Europe Ltd | Construction | 2019 |
| Spick and Span Cornwall Ltd | Administrative & support | 2025 |
| Spick and Span Peninsula Cleaning Services Ltd | Administrative & support | 2024 |
| ST Aubyns Property Limited | Financial services | 2013 |
| ST Erney Land Limited | Real estate | 2022 |
| ST Martins Court (Liskeard) RTM Company Ltd | Households | 2019 |
| ST Martins Meadow (Liskeard) Management Company Limited | Households | 2008 |
| ST. Aubyns (Looe) Management Company Limited | Households | 2008 |
| Stable Vast (UK) Limited | Real estate | 2017 |
| Starter Space Ltd | Real estate | 2017 |
| Station Body Repairs Limited | Wholesale & retail | 2019 |
| Stationfields Flat Management Limited | Real estate | 1991 |
| Steps Financial Services Limited | Financial services | 2012 |
| Sterts Theatre CIC | Arts & recreation | 2024 |
| Steve Hoskin Plant Limited | Construction | 2015 |
| Stevens Developments SW Ltd | Construction | 2021 |
| Stokes & Thorne Automotive Ltd | Wholesale & retail | 2019 |
| Stoneleaf Limited | Households | 1989 |
| Stove Shop (S.W.) Limited | Wholesale & retail | 2006 |
| Stray Dog Games Ltd | Information & communication | 2023 |
| Studio Latibule Ltd | Extraterritorial | 2019 |
| Sunrise Commercial Solutions Ltd | Professional & scientific | 2014 |
| Superspa Limited | Construction | 2004 |
| Sureore Ltd | Information & communication | 2026 |
| Swbeans Limited | Wholesale & retail | 2023 |
| Swift Home Solutions Limited | Real estate | 2025 |
| Systemlite Limited | Construction | 1995 |
| T Bellingan Limited | Health & social care | 2014 |
| T H C Carpentry Limited | Construction | 2014 |
| T.M Property Maintenance Ltd | Manufacturing | 2025 |
| TA Hicks Electrical Limited | Construction | 2015 |
| Tack & Trinkets Limited | Wholesale & retail | 2025 |
| Talbot Pipelines Limited | Professional & scientific | 2009 |
| Taliesin Education Limited | Education | 2006 |
| Talons Owltimate Encounters CIC | Arts & recreation | 2018 |
| Tamar Country Cars Limited | Wholesale & retail | 2005 |
| Tamar Estates and Auctions Limited | Real estate | 2024 |
| Tamar Refinishing Ltd | Manufacturing | 2020 |
| Tamar Tyre Centre Limited | Wholesale & retail | 2014 |
| Tamar View (Garden Construction Centre) Limited | Wholesale & retail | 1997 |
| Tarc Developments Limited | Extraterritorial | 2021 |
| Taurus Bricklayers UK Ltd | Real estate | 2010 |
| Taurus Developments UK Ltd | Construction | 2009 |
| Taviton House Analysis Ltd | Professional & scientific | 2019 |
| Tax Processing Limited | Professional & scientific | 1994 |
| Taylor Electrical SW Ltd | Construction | 2024 |
| Taylor Tian Communication Ltd | Information & communication | 2018 |
| Taylors Motors (Liskeard) Limited | Wholesale & retail | 1945 |
| Tcgrealestate Ltd | Wholesale & retail | 2022 |
| Teacher Tools AI Limited | Information & communication | 2023 |
| Tegscoaching Ltd | Arts & recreation | 2024 |
| Terry's South West Limited | Wholesale & retail | 2005 |
| Tgbrands Ltd | Information & communication | 2025 |
| Thangvanthang Ltd | Real estate | 2025 |